Y型沸石在异丁醇齐聚反应中的催化性能

Catalytic performance of zeolite Y in oligomerization of isobutyl alcohol

异丁醇经脱水齐聚反应可生产无芳烃、无硫的清洁燃料油(C_(8)、C_(8)^(+)),是一条不依赖化石能源生产动力燃料的有深远发展前景的工艺新路线。本文利用X射线衍射(XRD)、扫描电子显微镜(SEM)、NH3-程序升温脱附(NH3-TPD)、Py-傅里叶变换红外光谱(Py-FTIR)和N2吸附-脱附等手段对具有不同酸性和孔结构的HY沸石进行了表征,并将其用于异丁醇齐聚反应,考察了沸石的酸性质、孔结构以及反应时间等因素对异丁醇转化率和C_(8)及C_(8)^(+)产物选择性的影响。结果表明:硅铝比(Si O_(2)/Al_(2)O_(3))为20.9的HY样品表现出最佳的催化性能,异丁醇转化率可达94%,C_(8)及C_(8)^(+)选择性将近90%;HY中介孔的存在有利于三聚物的生成,在沸石织构性质相似的情况下,酸量增加有利于提高异丁醇的转化率。反应后的催化剂在空气中煅烧后可重新恢复原有的催化性能。另外,与Hβ沸石相比,HY沸石催化异丁醇齐聚有更高的C_(8)和C_(8)^(+)产物选择性。

Isobutyl alcohol can be used to produce aromatics and sulfur free fuel oil (C_(8),C_(8)^(+)) through dehydration and oligomerization.It is a new non-fossil process for producing power fuel.In this work,HY zeolites with different acidity and pore structure were characterized by XRD,SEM,NH3-TPD,Py-FTIR and N2adsorption desorption and were used in the dehydration oligomerization of isobutyl alcohol.The effects of acidity and pore structure of the zeolites,and reaction time on the isobutyl alcohol conversion and C_(8),C_(8)^(+)product selectivity were investigated.HY zeolite with a Si O_(2)/Al_(2)O_(3)of 20.9 showed the best catalytic performance,and the isobutyl alcohol conversion and the selectivity of C_(8)and C_(8)^(+)reached 94%and nearly 90%,respectively.The mesoporous HY was beneficial to the formation of trimers,and for HY zeolites with similar textural properties,the increase of acid content was conducive to improve the conversion of isobutyl alcohol.The catalytic activity of deactivated catalyst could be recovered by calcination in air.In addition,compared with Hβ zeolite with similar Si/Al ratio and mesoporous properties,HY zeolite had a higher C_(8)and C_(8)^(+)product selectivity for isobutyl alcohol oligomerization.